The present disclosure relates to an optical unit, a light source apparatus that uses the optical unit, and an image display apparatus.
Recently, products adopting a solid light source such as an LED (Light Emitting Diode) and an LD (Laser Diode) as a light source used for a presentation projector or a digital cinema projector instead of a mercury lamp, a xenon lamp, or the like of the related art are becoming widespread. The solid light source such as an LED has advantages that its lifetime is long, a lamp exchange as in the related art is unnecessary, and it immediately lights up as the power is turned on.
For example, Japanese Patent Application Laid-open No. 2013-41064 (hereinafter, referred to as Patent Document 1) discloses a projection type video display device equipped with a light source apparatus including a solid light source and a projection unit. As shown in FIG. 6 and the like of Patent Document 1, the light source apparatus includes a solid light source 10, a rod integrator 20, a color wheel 30, and a lens holding member 200. As excitation light, blue component light from the solid light source is irradiated onto a light emitter 33 formed in the color wheel 30. Red component light and green component light are generated from the light emitter 33 onto which excitation light is irradiated, and red component light, green component light, and blue component light are emitted time-divisionally. A recess 210 through which the light emitter 33 passes as the color wheel 30 rotates is formed in the lens holding member 200. With this structure, a lens 93 can be provided near the light emitter 33 (paragraph (0058) etc. of Patent Document 1).